Often times, a funnel is used to transfer fluids from a container into another receptacle. This may include the transfer of automobile oil to the engine of an automobile. Alternatively, cooking fluids are often times required to be transferred from a large container into a smaller container.
The concept is the same in either environment in that a fluid is transferred by a funnel through a large intake opening into a small outlet opening for communication with a downstream receptacle. When this transfer is complete, the funnel used often collects a residue of fluid between the funnel's larger intake opening and its smaller outlet opening. Unless a cloth or paper towel is used to clean the interior of the funnel, the fluid collects in the funnel and is ultimately allowed to drip from the outlet opening.
This residual fluid then must be dealt with after the fluid has been allowed to be transferred to an unintended location. In addition, if a transfer tube remains connected to the outlet opening, the free end of the tube is also allowed to transfer residual fluid along an unintended path.